1. Field of the Invention
The present invention relates to an antenna apparatus. More particularly, the present invention relates to a multi-band antenna apparatus of a Pattern Overlapped Capacitor Antenna (POCA) structure.
2. Description of the Related Art
In a conventional wireless communication system, various multimedia services such as a Global Positioning System (GPS), Bluetooth, and Internet are provided. In this case, in order to provide an efficient multimedia service, a transmission rate for transmitting a large amount of data for the multimedia service at a high speed should be guaranteed. As a result, research for improving performance of an antenna apparatus in a communication terminal is performed because the antenna apparatus substantially transmits and receives data for a multimedia service.
Further, in the wireless communication system, in order to improve portability of the communication terminal, thickness and size of the communication terminal should decrease. When at least a portion of an antenna apparatus such as a road antenna or a helical antenna protrudes from outside the communication terminal, the communication terminal cannot be easily carried and the antenna apparatus may be frequently damaged. Thereby, a built-in antenna apparatus in which the antenna apparatus is mounted within the communication terminal is embodied.
However, with the built-in antenna apparatus within the communication terminal, the antenna apparatus resonates at a relatively narrow frequency band. Consequently, as the communication terminal provides a plurality of antenna devices, an extended frequency band can be used. However, it is difficult to decrease the size of the communication terminal. That is, it is impossible to use various multimedia services in various wireless communication systems through a single antenna device in the communication terminal.
Therefore, a need exists for a multi-band antenna apparatus and a method for extending a frequency band.